user
Given a sentence, detect any errors in grammar and punctuation.

Additional Context:
"The movie that I saw yesterday was not what I was expecting, it was bad."

Answer:
assistant
This sentence contains an error in grammar - there should be an additional "it" at the end of the sentence - "The movie that I saw yesterday was not what I was expecting, it was bad it.". There is also an error in punctuation - there should be a comma between "bad" and "it" - "The movie that I saw yesterday was not what I was expecting, it was bad, it."